Improvement in packing projectiles for rifled ordnance



B. .B." HOTCHKISS;

Projectile. I

' 2 SheetsSheet 2 B. B. HOTCHKISS.

Projectile. N0. 5 0,357. Patented Oct 10, 1865.

" UNITED STATES PATENT OFFICE.

B. B. HOTOHKISS, OF NEW YORK, N. Y.

IMPROVEMENT lN PACKING PROJECTILES FOR RlFLED ORDNANCE.

Specification forming part of Letters Patent No. 50,357, dated October10, 1865.

nance; and' I do hereby declare that the fol-- lowing is a full andexact description thereof, which has been prepared with a view to theobtaining of Letters Patent therefor.

My invention relates tothat class of projectiles which are provided withpacking adapted to expand to fill the gun and to take the form of therifle-grooves; and it consists in certain means of preventing theexpansible portion from ringing or twisting around on the main body; inmeans of providing passages for the propelling gases past the packing torelieve the gun and ignite the fuse of the projectile when explosive; inmeans of causing the expansible portion to adhere or cling to the mainbody, and in means of partially protecting the rear edge of the packingor expansible portion from being injured in handling and transportation.

My invention differs radically from the previously-patented inventionsknown as the' Hotchkiss projectile in the fact that the cap employed inthe previous projectiles at the rear end to wedge open the packing andgage the extent to which it may bemade to expand is entirely dispensedwith, and the expansion is induced by the direct action of thepropellingcharge.

The main body of my present projectile is a single casting. It isrecessed to allow the l0cking thereon of the expansible packing-rin g.The latter is not a continuous ring expansible alike all around theprojectile, but, on the contrary, is interrupted and bridged across atoer-- tain points by the main body of the casting, so as to presentabroad shoulder to prevent ringing and to materially interfere with orentirely prevent the expansion of the packing at those points, andinsure a passage for the flame past the packing at those points. Thepacking is continued past those points, but in a different form, and bypreference at a place or places nearer the axis of the projectile, so asto obtain the desired unity and strength in the packing to enable it tocling to the main body. I extend the metal of the main body fartherrearward at those points, and thus am able to drop my projectiles on thefloor or to strike them together or otherwise subject their rear facesto considerable violence without bruising the edges of the packing,because the concussion is received on the extensions or legs of the maincasting instead of on the packing.

Such being the nature and objects of the invention, I will proceed todescribe more in detail the manner in which the invention is carriedinto practical effect by reference to the accompanying drawings, and toletters and numbers denoted thereon.

Similar letters of reference indicate like or corresponding parts in allthe drawings.

Figure 1 is a longitudinal section of my projectile before its packinghas been expanded, and Fig. 2 is a duplex figure, showing my projectileafter its packing has been expanded; the lower half representing a rearview and the upper half a cross-section on the line S S in Fig. 1.

A is the main body, of cast-iron, and O is the expansible packing, ofbrass. A A A are legs from the main casting A, which extend rearwardacross the packing O and a little distance beyond or rearward of thelatter.

0 O G are stout shoulders in the packing C, adapted to press fairly andsquarely against the corresponding sides of the legs A to resist thetendency of the packing to ring or slip around on the projectile whendischarged from a gun with quick rifling.

O O O are parts of the packing ring 0, which extend across inside of thelegs A and unite the packing in a single but not circular piece,extending quite around.

A A A are parts of the main body A, which extend rearward within ornearer the axis of the projectile than 0 The parts A are stronglyjoined'both to the main part A and the legs A, and strengthen the whole.A, A and A are cast together.

0 is an internal flange near the front edge of the packing. It extendsinto a correspondin g recess (circular groove or rabbet) provided inthemain body, as represented. A isa flange or overhang extending from themain body into the rabbeaand aiding to lock the packingring upon themain body. In manufacturing my projectile, I first produce by propermolds and cores the casting A, with its several projections, A, A and Aand with its groove or rabbet, as indicated, and afterward cast'thereonthe more fusible packing 0, G 0 and G The packing may be of other metal,but I prefer soft brass. It maybe coated or shielded on its outersurface with a softer metal or alloy, or with fibrous or greasymaterial, and may be caused to partially amalgamate or solder to thecasting A byawell-known means; but I do not consider such usuallynecessary.

G O G are additional connections of the packing material 0 across theinner side of the legs A A A. Each connects near the rear edgeof thepackingin the manner represented. They may be omitted without seriousdetriment. I make the exterior of the packing 0 correspond in diameterwith the exterior of the main body A. in such condition, but when thegun is discharged the great pressure of the ignited powder of thepropelling-charge acts on the inner surface of the packing O, andexpands or increases its diameter so as to till the grooves of the gunand compel the packing-ring to rotate and follow the spiral path of thesame. In

doing so the shoulders 0 press fairly againstthesides of thelegs A,supported by the braces A and compel the entire projectile to assume thesame motion. But that portion 0 of the metal of G which is within thelegs A cannot radially expand outward, being forbidden by the presenceof the legs A, so that the packing does not expand all around theprojectile, but leaves the places A A A, so that the gases may flowalong through the spaces there provided between the legs A and the innersurface of the gun to ignite the fuse at the front. The channels thusprovided for the gases may be hollowed out to increase their capacity,if desired.

Fig. 3 is a longitudinal section, and Fig. 4 a rear View, of a differentform of my invention. In this form the legs A are extended still fartherrearward, and the supporting portion A is enlarged and extendedrearward, so as to materially change the proportions of the projectile;but the novel features of my invention will be recognized.

Fig. 5 is a longitudinal section, and Fig. 6 a

It is introduced in the gun rear view, showing another form of myinvention. In this the bracing portion A are less than in the form lastdescribed, but greater than in the first form, or, rather, they areextended directly across the rear of the projectile, so as to bestronger. The chief feature in this form not before described lies inthe lip 0 extending forward from the inner edge of the part 0 of thepacking. It extends into a recess cored for it in the casting A, as willbe apparent, and locks the packing still more effectually to the body A.A similar lip, 0 extendingquite alongthe lip 0 orin points thereon, asdesired, may be used on the other forms of my projectile, as indicatedslightly in red outline on the other figures.

It will be observed that in Figs. 3 and 4 the legsA extend much fartherin rear of the packing-ring C than in the other figures. This is donemainly to afford a longer and better hearing for the projectile in thegun.

Figs. 7 and 8 represent a modification of the form shown in Figs. 5 and6, Fig. 7 showing the condition of the packing-ring before firing, andFig. 8 its condition after firing.

M is a quantity of grease, which is forced out when the packing isexpanded.

Having now fully described my invention, what I claim as new therein,and desire to secure by Letters Patent, is as follows:

1. The bridges or posts A, extending across the packing flush with thesurface of the main casting A, and adapted to allow windage at thosepoints, substantially as and for the purposes herein set forth.

2. Prolon gin g the legs or posts A in the rear of the packing C, so asto protect the latter in handling and transportation, substantially inthe manner and for the purposes herein set forth.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

THOMAS D. SrETsoN, D. W. STETsoN.

